Dental prophylaxis instrument



y 1970 R. P. SPINELLO 3,509,630

DENTAL PROPHYLAXI S INSTRUMENT Filed July 1. 1966 4 FIGJ 1 15 I 11 INVENTOR Rmaza f? Spz'flella 5r MK Kim Q m. a2"; ATTORNEY? t a cleaning compound, adapted to be attachednto a r tary dental tool and in whicli th is eccentric iin rotary mot on to perform th functions ofmoving the cleaning oompoundintoatooth H cleaning tip and vibrating the unit to cause .the cleaning at tipto vibrate on the tooth. A flexible coupling vbetween y a the rotary dental tool and the cleaning tip affords Yib fa torytrnotion of @16 instrument and; also allows the open- I up, but often results ment. Also, paintul ht-atingtof the tooth surface can amounts of cleaning compound can bfiwbrqughtyto the dental prophylaxis instrument which can be expendabl ABSTRACT on DISCLOSURE dental prophylax ;instrument; andwcontainerj for ator to control the rate of cleaning compound discharge.

This invention relates to a dental prophylaxis instru:

ment in and; more particularly, to a powerdriven unit which performs the multiple functions of feeding a clean:

ing compound to the teeth and imparting motion to a cleaning element.

Inaccordanoe withstandard techniquesin dental otfices;

teeth are cleaned by providing a high-speedtr otary abrading or cleaning member, such as a bristle brtish or ayruba d,

ber cup used in conjunction with a cleaning compoun such as a pumice slurry; The compound isyytypicallywcart-t tied to the teeth by repeatedly dipping thenabrading memw her into an individual cornpound container: nearby. This I hue-consuming in its nrtial set-v splattering of the cleaning 0 y q procedure not only is pound on thekpatient, th operator and the In;

which overcomes the abovedisadvantageszof conventional equipment and which i jst capablet of dispensing its own supply ofcleaning COlTlpOUl'ldn a i t Another object at of t the; invention is to providea dental prophylaxis instrument; in which precisely metered tooth surfaces while their cleaning: operation fiis taking: place.

Still another object of the invention: is to; providea dental machinery.

Still; another object of the invention is totprovideaa for each patient treated, but which can, if desired, vb

sterili ied and reused t t t t t i In accordance with the present invention a convene tional rotary driving unit, such as the ihand npiece of la" dental drill having a rotary; shaft coupling atits end, can be used to actuate archiving and feeding assembly in the formuof a radiallywolfset member arranged Wlt a housingt' to impartfivibratory motion: thereto. i In one preferredembodirnent of the invention this assemblyt can takes the form of a helical spring which is; eithe angled on weighted towbe dynamieally unbalancedpon both, sowthatritsfree endswhips around within'the thoufs-y:

ing, which is resilicntlysupported. This resilient sup Claims t j Accordingly, it is oneobject of the present invention to provide an improved dental prophylaxisinstrument i ll dm ti causes hither a oth's t Th abo e and other features and objectsof thenpresent invention will be apparent from thefollowing specification describedpreferredi embodiments thereof taken in conjunction with the accompanying drawing in which: p EI GURElds a view iri longitudinal section showing in broken lines the? conventionalpower-driven hand iece s t normally used inheritalotfices andflshowing in full lines I coupled thereto a Icleaning attachmentfiformed in accord ancewith thelpresen invention; t 1 i 3 H FIGURE 2 is a sidenviewtofgthe internal rotor of thet 1 cleaning attachmentm t t i 1 t FIGURE 3Cisf a View t in longitudinal section showing an expendable, or ifldesired reusable portion of the cleaning attachment(containing its: zowntcharge of cleaning compound, in axformnin which it mightvbe receivedqihy 35 a dental: ofiice and n-divs. 1 t i Referring to the drawing, the in ventio n is illustrated as t ernbc died in a unit 10 adapted to be attachedtto the hand 3 piece 11 of a conventional dental tool of the" type to which,

drill o r rotaryfcleaning element re normally att i y t 13 and piece l lt in cljudefs an nternalflchatnbe i g a rotary cpuplingllig adaptedtomeceive is tobe rotated he outerxtigl i of the hancltp s a bearingtor uiding the; Shaft to be rotatedtand, n epresentsinvent on sthe rotated shaft cornprisesma t short shaft element 15 clu dingtllall nner end 15a adapted a to berecei ed in the coupling or cnuck 13 and an outer end 15b adaptedttoucarry a driving and pumping element 16 preferably takingthegform o f a helical spring,

The shaft sections15a and Edam/separated by a bush t ing or seal elementi17 which, as best seen inFIGUREll abuts closely :ag llstt ht fipenend of1the hand Piece ndwhich tclosely engages Itheshaft lstotfprma seal. Preferablythe bushing or, seal 17 can be held istati nary whileflthe shaft lS rotates therei The: free or? ou teren a of the elementl filishenttto for entangle mWithIQSPeCt to the axis of the shaftllSQthis angle lbeing atfunction of t a [the spring constant orl stiffness i;

rive dimensions ofi the tpartssand egree iof oleanin ac desired; all:aswdesoribedilater his, angle pan bcy, duced undergsta t ditions hy bendingonlif desi can COmt il'ljt Q ic ng under dynatln C0 'ditionsbY l it rnically unbjy 'ng he felernent illa t me an angle when d y a adapted to engage the teeth and whichcan take the form of a rubber nozzle havinga divergent or flaringtip 19a and a central channel 19b communicating with the interior of the cylindrical housing 18. The internal diameter the pumping and driving element 16, under rotation, bears laterally against its internal wall to impart vibratory cleaning instrument is illustrated in the form in which it is normally furnished to. the dentist with the nozzle or vibrating tip 19 carrying a removable plug 21, and with the innerend of the flexiblecoupling20 folded back upon itself to form acutf 22. A removable plug 23 is inserted in the cult to contain a supplyyof cleaning compound 24, such as a pumice paste, or alternatively the end can be pinched closed, clipped or taped. T o assemble the apparatus for cleaning teeth, the dentist inserts the drive element shown in FIGURE 2 with the shaft end 15a received within the end, piece 11 to engageqthe coupling 13 and the plasticbushingor seal 17 l iearingysnugiy againstthe tip of the hand piece in sealing relationshipt 4 and to afford the operator amore comfortable, lessagitated finger grip.

It will be understood that the flexible coupling 20 permits the housing 18 and tip 19a to vibrate laterally in relation to the axis of the hand piece at a rate which is directly proportional to the axial rotation of the shaft 15.

The lateral resilience of the spring element 16 precludes heavy jarring or hammering action of the cleaning member 19 in any direction including normal to the tooth surfaces. The seal 17 effectively prevents theabrasive cleaning compound from moving backwardly into the bearings of the hand piece 11 either through the space between the shaft and the center hole in the seal 17 or through the space between the flexible coupling and the outer edge of the seal ,17. Because the flexiblecoupling was initially folded back upon itself in a cuff before the unit was attached to the power source, that portion of the flexible coupling will be free of cleaning compound at all times.

In operation, under high speed rotation, a number of convolutions of the'element 16 will be/drilven, due to its being bent (which inturn creates dynamic imbalance),

against the wall of the housing 18 by: centrifugal force The plug 23 is removed from the flexible coupling 20 which is slipped over the bushing 17 until the free end of the drive and pumping element 16 engages or is dis posed close to the end of the housing 18. The cuff portion 22 is then unfolded and snapped over the end of the hand piece 20. The cleaning assembly is ready to use when the dentist removes the tip plug 21 from the cleaning element or nozzle 19. The volumeof cleaning paste 24 within the housing is preferably so arranged that, when the drive shaft 15 is rotated (by means for example of a footcontrolled rheostat R which energizes themotor M), the

pumping anddriving element forms a cavity within the housing free of cleaning compound without driving significant amounts of the compound out through the tip19.

To begin the, cleaning operation, the dentist brings the tip 190! against a tooth surface andsqueezes the flexible coupling 20 in the area between the seal 17 and the housing 18, thus causing a small amount of the cleaning compound to come Within the space swept by the helical spring 16 to be expressed from theitip 19a. The cleaning element 19 is meantime being driven in a vibratory cleaning action on the tooth surface. Because there is no highspeed rotary peripheral velocity of the tip 19a, the cleaning compound is not thrown out by centrifugal force and splattering is avoided. The cleaning action is continued until the majority of the cleaning compound 24 has been expressed from the top19a under the control of the finger and thumb pressure of the operator squeezing on the flexible coupling 20. The volume of cleaning compound expressed at any given time is under the control of the operator who holds the implement between the thumb and forefinger at the squeezing point of the resilient sleeve 20, with hand piece 11 of the power unit being carried in the crotch of the thumb and forefinger like a pencil. To insure the most elfective control, in accordance with the invention,

the helical element 16 is disposed forwardly, for the most relatively few turns pick up and propel the cleaning compounds at any given time. As the squeezing actiongcorns presses the sleeve againstthe shaftextension 15a, virtu ally the full charge of, cleaning compound will be ex pelled drop by drop In additiomit is preferred that part of the shaft 154 in the squeezing area be free of. screw propelling surfaces both to avoid abrasion on the sleeve to slide around the cylindrical surface to impart vibratory suchifactors as the angled and the, spring force, one or more convolutions can touch the wall when there is no rotation; The light forcewapplied to theinstrument by l the operators handholdsthecleaning element 191011 the toothsurface against the vibratory force which could otherwise, introduce a component of perceptible: motion normal to the surfaceoThe helical spring element yields to the holding force but there results a cyclically varying pressure normal to the tooth surface which is believed to augment the cleaning action. Also, the exact nature of the cyclical pressures and motions of the cleaning tip 19 against the tooth can be varied by virtue of the ability of the flexible coupling 20 to bend, creating an angle between the axis ofthe shaft. 15a and the axis of the cylindrical housing 18. This causes heavier cyclical. pressures against the tooth and diminishes the forces away from the tions of the flared cleaning element vibrating in translation and expanding and contracting under cyclical pressure change, together with the superimposed motions of the operators hand, all contribute to the cleaning action. In all cases, the severe heating of tooth surfaces which normally occurs with the use of rotary abrading devices is avoided.

While the invention has been described above having reference to a preferred embodiment thereof, it will be understood that it can take various other forms and arrangements within the scope of the invention; For example, rather than using an inclined helical spring, a straight but eccentrically weighted helical spring can be used, both being effectively dynamically unbalanced. Also an angularly inclined shaft portion or cam can be used and to more closely approximate the action of the helical spring, the shaft or cam can be formed of resilient material, or resiliently mounted, to avail of the dynamic characteristics and to soften vibrating action on the tooth surfaces, particularly in directions normal thereto. In such cases, inclined planes or surfaces such as screw threads can be used to propel thexcleaning compound axially from the reservoir to the cleaning element. Also, various other types of cleaning elements, such as bristle brushes having hollow cores, can housed in place of the soft rubber cup 19'. The invention should not, thereforebe recompressed to express cleaning compound from the chama:

. bring cleaning compound into. the orbit ofttravelof sai helical. convolntions thereof. 1 1

,motion at the other endfrom a handpiece, anda tcircular sealing member between the ends of theinner shaft within to be coupled to the handpiece and having a drive por tion eccentrically disposed in rotary motion, a. housing surrounding the eccentric portion of the rotary core. and adapted to be drive in vibratory motion by the drive portion upon. rotation of the core, a tubular flexibleucoupling to join the housing to the handpiece and forming a charm her for a cleaning compound, a toothccleaning member carried by the housing and movable therewith; and means a forming a passage from... the chamber to the cleaning ele 6 ment, whereby the coupling. can be manuallyflradially.

a UK

her and also affords relative motion between the housing and the handpiece...

2. Apparatus as set forth in claim 1, saidcrotary core 6 portion including inclined surfaces to drive cleaning com} pound toward the cleaning member when rotated.

3. Apparatusyas set forth in claim 1, said eccentrically disposed portion of thegCOIe comprising a radially. resilient member.

4 Apparatus as set forth. in claimtl, said eccentrically 0 disposed portion of the corebeing dynamically unbalanced w a and radially resilient.

5. Apparatus as set forth. in claim 1, said eccentrically disposed portion comprising a helical spring element e011. 1: pled. at one end to a rotary shaft and dynamically unbalancedat its free endto be whipped against the interior of the housing to effect vibratory excursion of the tooth cleaning member. 6

6. Apparatus asset forth in claim 5, said housing being, circular in cross section .and substantially. rigid, and said tubular flexible coupling being adapted to. be lsqueezedhto spring element to. bediiven out of said ehamber by the al 7. Apparatus as set forth in claim 5, said rotary core portion including an inner shaft portion carrying said heli3- cal spring at one end and adapted to be driven in rotary which the shaft rotates in sealing relationship and adapted toengage the tubularzflexible conplingat itsouter edge in sealing relationship, thereby to seal the cleaning com pound from the handpiece said sealing. member being axially spaced from therigid housing to define a flexing 1,335,825 i l/ 19 20 1 1,904,710. l/1 93351 area affording vibrational movement of the housing and also a squeezing area to be compressed radially .1 to urge cleaning compound into the orbit of the helical spring member.

8. Apparatus as set forth in claim 5, said cleaning element comprising a resilient member having an outwardly flaring tip portion and a central bore defining direction and to] impart radial vibrationto a dental clea ing member operable in conjunctionwith the compoun fpoundf axially with jrespect to the inner shaft by gthe whi pping actio ofthepflexible mentw llaApparat portion comprising a elical springdisposed' substan lyl coaxially with theinnlerj shafrat the point ;of attac circular sealing jdisc bh the inner fsliaft between itsend said shaft being rotatably received. thereinin sealing latioiiship. t

9. A dental prophylaxis instrument. adapted towbe "driven by a rotaryhandpiece comprising atubularhous .ing having a circular interior. cross section, a flexible 1 coupling to joinithe tubularqhousing .to. the .handpiece and a rotary core portion adapted to be driven by thel hatidpiece and extending into the tubular honsingflthe. rotarycoreincluding at its endqwifthin the tubular house 1 6 .ing a cantileveredahelical springsupportedand rotated? 6 by its inner end andhaving its free enddynamically unbalanced with=respect;to the. axis of rotation-and d adapted to engage ther circular interiorwall under, .1 centrifugal forcesfto vibrate the housing under resilient pressure. i 1

10..Asan articlelofmanufactlre; a rotary core piece. adapted to pump dental cleaning. compound in anaxial comprising aisubstantially rigid inner shaft portion .hav ing an end adaptedtmbe coupled to and driven win rotary motionby a rotary dental tool,zand an elongated head portion having a flexible, radially oifset cantileversupported pumping element attached to the other end of the inner shaft portion and: including inclined sur-- faces on said element to expel flowable cleaning com-:3

claim 510,

merit and inclined away fromxfthe axis ofthe sha t. at its free end. 6

12. Apparatus as. set forth=infclaim 11 including a .5 References Cited 3,389,468 6/1968 Lewis et al. 32-59 ROBERT PESHOCK, Primary Examiner 

